Ok, I've been doing some quick tests with fan profiles in MSI Afterburner during Steams VR test.
Stock profile for this GTX980ti (I think it's a Zotac Reference) temps hover at 83 degrees C, and yields a 10.7 performance score on the Steam VR test. 11.600 frames tested. 0 below and 0 bound.
Interestingly, creating a slightly harder fan profile, stating 100% fans at 85 degrees C (max temp before GTX980ti throttles) yields a 77 degree C max temp on the card during the test, an 11 performance score, and I think around 12200 frames tested. 0 below and 0 bound.
So, in conclusion, installing MSI Afterburner and creating a slightly harder fan profile (setting max fans at max gpu temp before throttling) will give you tangible yields in VR, and performance in general I presume.
Gfx fans will of course be a bit more noticable, kicking in harder earlier, but hey, it's all about performance right.
I know this is nothing new to many of you, but I've never really dabbled in this area before, so I'm having a blast.
Fly safe all.
Edit: and based on these findings, the card is already throttling at 83 degrees, so should probably be kept under 80?
2. Edit: all other settings are stock.